I needed to re-do the HSC 2 Unit maths and physics whilst I was completing my Aviation degree, to get better marks (at the time was thinking of joining the military).
I did some distance ed courses thru Central Queensland University (CQU)called Transition Maths I and II, and Intro Physics which I was able to get resognised as being equivalent to first yr maths and physics at University level, and they were counted as subjects towards my degree.
They weren't that expensive either, but luckily I was able to get a scholarship thru CQU that paid for them!
Have a look at :
http://facultysite.cqu.edu.au/FCWVie...File.do?id=632 for maths, and
http://fseh.cqu.edu.au/FCWViewer/vie...vpAe?page=2147 for physics.
They were self paced also, so no time limits, and you only had to sit an exam at the end if you wanted to be able to claim credit for the subjects at university, or you needed to present a pass to someone like a military selection board. If you are just looking to brush up, then you just did end of subject tests that you posted to them, and they posted you back your results.
Hope this helps!
Cheers